Microstructural and mechanical properties of organic surfactant templated nanoporous thin silica films have been studied by X-ray diffraction, Fourier transform infrared spectroscopy, and nanoindentation. Compared with many other porous low-k dielectrics, the self-assembled molecularly templated nanoporous silica films demonstrate better mechanical properties. This is ascribed to the presence of a well-ordered pore channel structure in the nanoporous silica thin films. Hardness and elastic modulus are strongly dependent on film preparation and modification methods. Trimethylsilylation by hexamethylsilazane vapor treatment effectively enhances the mechanical strength of the nanoporous silica films. When the sol precursor solution is mixed with trimethylchlorosilane ͑TMCS͒, the resulting nanoporous films have a weaker mechanical strength. The pore channel structure of the nanoporous silica film becomes less ordered for the TMCS derivatized nanoporous films. In addition, the chemical structure in the silica solid matrix of the TMCS derivatized films is more disordered than those without TMCS modification. The nanoindentation measurement results are discussed in terms of the pore microstructure of the nanoporous silica network and the springback effect due to the presence of trimethylsilyl groups in the nanopores.

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The triblock copolymer Pluronic P-123 ͑P123͒ templated silica films were deposited by spin coating on p-type silicon ͑100͒ wafers. Trimethylchlorosilane ͑TMCS͒ was added to precursor silica sols to provide the necessary hydrophobicity for the resulting silica films. The dielectric constant and leakage current density of in situ derivatized mesoporous silica films were found to decrease with increasing concentration of TMCS in precursor solutions. The precursor aging time was found crucial on the surface morphology and reliability in dielectric properties of mesoporous silica films with ultralow dielectric constants of 1.7-2.1.

A qusai three dimensional aluminum metallic photonic crystal (Q-3D Al MPC) composed with five layers of Al rod arrays was fabricated from IC foundry. The qusai means that MPC was made out under constrain of the traditional metallization processes in IC manufacture during current foundry model, in that the vertical distance between layers is about 1 µm while the horizontal pitch is about 350 nm. The aim of this study is to evaluate the feasibility of mass production of MPC by using the modern IC technology. The novel optical properties are investigated in order to estimate the photonic band gap (PBG) behavior under this qusai structure. There exists an obvious PBG effect ranging from 3.5 to 7.5 µm and some other sharp period of transmission region.